Follow-up of a Cohort of Patients With Myasthenic Syndrome and COVID-19 Infection

Follow-up of a Cohort of Patients With Myasthenic Syndrome and COVID-19 Infection: Consequences on the Severity of Myasthenic Syndrome and Reciprocal Impact of the Two Pathologies on Their Respective Treatments

Coronavirus disease 2019 (COVID-19), declared by the World Health Organization (WHO) as a "public health emergency of international concern" (January 31, 2020), has posed a significant threat to global health. This infectious disease, caused by the 'severe acute respiratory syndrome coronavirus-2'(SARS-CoV-2), was first reported in China at the end of 2019. As other coronaviruses, SARS-CoV-2 primarily targets the human respiratory system. The most common symptoms are fever, fatigue, and dry cough. During the second week of the disease, part of patients may progress to shortness of breath, then hypoxemia and severe pneumonia. Acute respiratory distress syndrome (ARDS), linked to some risk factors such as advanced age and underlying comorbidities (hypertension, diabetes, cardiovascular disease, and cerebrovascular disease), may be fatal and needs early supportive therapy and monitoring.

Some patients with COVID-19 experienced neurological complications including headache, dizziness, hypogeusia and/or anosmia, altered level of consciousness, strokes, seizures, and ataxia, less frequently neuromuscular disorders (NMD) such as acute inflammatory polyradiculoneuropathy. Among NMD, myasthenia gravis (MG) patients, particularly susceptible to infections causing crises, could be of special risk of COVID-19 ARDS. Some general recommendations were established for the management of NMD during the COVID-19 pandemic,with also specific recommendations for MG. However, only data on a small number of patients who were managed in hospital are currently available;in addition, only two cases of myasthenic crisis following COVID-19 were reported. For this reason, the French neuromuscular rare disease network (FILNEMUS: 'FILière NEuroMUSculaire') has created the 'CO-MY-COVID register' to describe the clinical course and prognosis of patients with COVID-19 and pre-existing myasthenic syndrome.

Coronavirus disease 2019 (COVID-19), declared by the World Health Organization (WHO) as a "public health emergency of international concern" (January 31, 2020), has posed a significant threat to global health. This infectious disease, caused by the 'severe acute respiratory syndrome coronavirus-2'(SARS-CoV-2), was first reported in China at the end of 2019. Nowadays, with the exception of Antarctica, COVID-19 is a worldwide pandemic that continues to spread around the world (8,065,966 known cases and 437,604 deaths in June 16, 2020; https://gisanddata.maps.arcgis.com/). As other coronaviruses, SARS-CoV-2 primarily targets the human respiratory system. Its most convincing mode of transmission is inhalation of infectious aerosols or direct contact of infected people's droplets. The most common symptoms are fever, fatigue, and dry cough. During the second week of the disease, part of patients may progress to shortness of breath, then hypoxemia and severe pneumonia. Acute respiratory distress syndrome (ARDS), linked to some risk factors such as advanced age and underlying comorbidities (hypertension, diabetes, cardiovascular disease, and cerebrovascular disease), may be fatal and needs early supportive therapy and monitoring.

Some patients with COVID-19 experienced neurological complications including headache, dizziness, hypogeusia and/or anosmia, altered level of consciousness, strokes, seizures, and ataxia, less frequently neuromuscular disorders (NMD) such as acute inflammatory polyradiculoneuropathy. Among NMD, myasthenia gravis (MG) patients, particularly susceptible to infections causing crises, could be of special risk of COVID-19 ARDS. Some general recommendations were established for the management of NMD during the COVID-19 pandemic,with also specific recommendations for MG. However, only data on a small number of patients who were managed in hospital are currently available;in addition, only two cases of myasthenic crisis following COVID-19 were reported. For this reason, the French neuromuscular rare disease network (FILNEMUS: 'FILière NEuroMUSculaire') has created the 'CO-MY-COVID register' to describe the clinical course and prognosis of patients with COVID-19 and pre-existing myasthenic syndrome.

Inclusion Criteria:

• 1. Child or adult patients, living or deceased, presenting or having presented a myasthenic syndrome and a COVID-19 infection 2. Myasthenic syndrome is established by:

  • Either the presence of a specific antibody

  • Either the presence of specific electrophysiological abnormalities

  • Either an evocative symptomatology improved by a therapeutic test with an acetylcholinesterase inhibitor

  • Either one or two pathogenic mutation (s) in a gene involved in congenital myasthenic syndromes (dominant or recessive disease).

    3. COVID-19 infection is established by

  • Either a positive PCR test

  • Or a specific chest scanner

  • Either a positive serology

  • Either a clinical syndrome of COVID-19, validated by a committee of experts. 4. Patients affiliated or beneficiaries of a social security scheme 5. For living patients: patients who have been informed of the study and have not exercised their right of opposition or parents or holders of parental authority who have been informed of the study and have not exercised their right opposition.

For deceased patients: beneficiaries or parents / holders of parental authority having been informed of the study and not having exercised their right of objection.

Exclusion Criteria:

1. Persons placed under judicial protection